Satellite communications system for providing global, high quality movement of very large data files

ABSTRACT

A system for providing communication services between geographically disbursed source and destination terminals includes at least one airborne or spaceborne wireless communication device, such as a satellite. The wireless communication device is configured to store and forward large data files of at least an aggregated 10 gigabytes. The wireless communication device includes a wireless transceiver for communicating with the source and destination terminals over at least one high bandwidth channel. A mass data storage device stores the large data files for a predetermined period of time that is greater than approximately two minutes. At least one processor is coupled among the mass data storage and wireless transceiver. The processor is configured to control receipt of a large data file from the source terminal and to transmit it to the destination terminal as the wireless communication device nears the destination terminal.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a divisional application of U.S. patent applicationSer. No. 10/530,018, filed on Apr. 1, 2005 which is a U.S. NationalPhase application of PCT/US2004/015154, filed on May 14, 2004, whichclaims the benefit of U.S. Provisional Patent Application No.60/473,744, filed May 27, 2003 (attorney docket number 34716.8001.US00)all which are incorporated herein by reference in their entireties.

BACKGROUND

Currently excellent digital data transfer services are available in wellconnected areas where fibre-optic networks and new terrestrial wirelesstechnologies permit the movement of very large volumes of data at veryhigh speeds. However this level of sufficient telecommunicationsinfrastructure is primarily limited to densely populated areas of theworld.

Existing geostationary earth orbit (GEO) satellites do providerelatively high data volume transfer services but are inherently limitedto specific regions, with coverage typically over or near land only.Most of these also provide much lower data rates as their goal is toservice large numbers of users each demanding a relatively smallercapacity. There are very few wideband transponders as most are limitedto about 72 MHz, and even these would require a large antenna to operateat the necessarily high data rates to transfer massive volumes of data.

Although timeliness of delivery for small (i.e. up to tens of megabytes)data files is generally fast, the same is not true for larger data fileswith such transponder bandwidth or antenna size limitations. In additionthis method places costly equipment requirements on the user, andtransponder capacity required for very large data files is typically notavailable on a consistent, long-term basis. Furthermore the timerequired to transfer such large files at these bandwidths requires along and uninterrupted connection making such methods especiallyimpractical for shipboard or mobile use. Moreover, many of such existingsystems induce errors in the act of transmitting the data, which attimes can amount to substantial losses of data in such a large datatransfer.

Even the data volumes supported by new internet satellites is generallylow, as they are designed for asymmetric internet-type usage with slowtransmit rates and high receive rates. As such, internet satellitescannot support the data rates required to transfer large data files in atimely manner. Additionally, as above, many of these satellites are GEOsatellites dedicated to large regional markets and subjected to certainregulations and/or technical hurdles.

In many cases the transfer of large data files is accomplished throughthe courier of physical media. Ignoring loss of transmitted packages,such couriers achieve a much greater rate of delivering relativelyerror-free data over the wireless transmission methods noted above.Further, such couriers can be considered more secure than wirelessbroadcast methods. However, access to conventional courier servicegenerally does not extend to remote areas, particularly in a timelymanner, and shipments are susceptible to large delays, such asprocessing through customs. The courier method for bulk data transfertends to be labour intensive and shuttling of physical media byhelicopter from ocean going vessels, while near shore, is extremelycostly and not practical farther off shore.

Many data sources and sinks located in remote areas do not, as of yet,have access to sufficient, or cost effective, services for the bulktransfer of data. Users in remote locations, with no viable options fortransferal of large volumes of data, where complex computations oranalyses are required are often forced to maintain significantde-centralized infrastructure and personnel to process the data on-site,which is operationally expensive when such options are even available.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1: A high level illustration of the service, in the context of aspecific embodiment (seismic survey service example).

FIG. 2: A high level illustration of the service, in the context of aspecific embodiment.

FIG. 3: A diagram identifying high level elements in the systemarchitecture for an embodiment of the invention.

FIG. 4: A simplified system payload block diagram showing technicalelements for the embodiment of the invention.

FIG. 5: A diagram of the end-to-end data flow method used by the systemfor providing service.

FIG. 6: A diagram illustrating techniques within the data errorcorrection method.

DETAILED DESCRIPTION

Aspects of the invention described herein are directed to a method andsystem to implement a digital transport service for very large datafiles, currently up to hundreds of gigabytes, with global point-to-pointcoverage for non-real-time applications, with virtually error-freedelivery in less than a day. This method and system is scalable astechnology makes advances in parallel with growing needs of the marketsthat are served. This system makes it possible to service a user need,for the timely movement of very large volumes of data from remote areas,that are not well served by existing or projected offerings such asexisting geostationary satellites, broadband terrestrial wireless orfibre networks.

One embodiment of the invention, that addresses the above service marketniche, is a store-and-forward fleet of small low earth orbit (LEO)communication satellites as elements of a system capable of providingbulk transfer services for large digital data files from small sizedremote ground terminals, on land or over water. This embodiment, basedon a small-satellite platform, focuses on such a file transfer (i.e.unlike complex multi-service communication satellites that supportreal-time and/or on-demand functionality) and therefore permits use ofseveral innovative method features that give rise to a simple andcost-effective system. The same embodiment can be adapted to alsoprovide ultra-high bandwidth near real time transfers. This would occurwhen both the source and destination terminals (or a relay terminal)were simultaneously in sight of the satellite. The data would betransferred from one to the other without the requirement for storageand subsequent transmission. Alternatively, intersatellite links may beemployed to establish a near real-time path.

The following description of the invention provides a thoroughunderstanding of, and enabling description for, the embodiment of theinvention. Some ancillary elements are included in the description ofthe invention, for reference and context. However, one skilled in theart will understand that the invention may be practiced without many ofthese details. In other cases, well-known system components andfunctions have not been shown or described in order to avoidunnecessarily obscuring the description of the embodiment of theinvention.

The terminology used in the description presented below is intended tobe interpreted in its broadest reasonable manner, even though it isbeing used in conjunction with a detailed description of certainspecific embodiments of the invention. Certain terms may even beemphasized below; however, any terminology intended to be interpreted inany restricted manner will be overtly and specifically defined as suchin this Detailed Description section.

At a high level, as shown in FIG. 1, the depicted embodiment of theinvention is a satellite communication system for the pick-up, storagein transit, and drop-off (delivery) of large digital data files fornon-real-time applications. This embodiment provides global coverage,with extremely high data fidelity, and data delivery times of less thana day. FIG. 2 shows the high level operational concept of a specificembodiment example, in particular a system (referred to in the diagramas “CASCADE™”) that provides an “express delivery service” for largedata files. It is noted that other embodiment permutations of thisexample are also feasible to implement the same or similar system andmethods. The invention has a number of innovative aspects, distinct fromother typical satellite communications systems, that are applicable inother fields. For convenience some features of the system and method aresummarized below.

Unless described otherwise herein, the blocks depicted in FIGS. 1 and 2and the other Figures are well known or described in detail in the abovecross-referenced provisional patent application. Indeed, much of thedetailed description provided herein is explicitly disclosed in theprovisional patent application; much of the additional material ofaspects of the invention will be recognized by those skilled in therelevant art as being inherent in the detailed description provided insuch provisional patent application, or well known to those skilled inthe relevant art.

1. Error-free data transfer. Through the use of pre-processing andpost-processing techniques, made possible by the non-real-time focus ofthe system, the probability of the system flipping just a single bit inuser data is less than ˜10 ⁻¹⁶. This level of end-to-end data quality isequivalent to the occurrence of only one bad bit during the delivery ofmore than 10,000 files where each of about 100 gigabytes. Thesetechniques employ the cessation of data flow when the channel degradesand feature multiple means to only replace relatively small erroneousdata blocks via a low bandwidth auxiliary channel. The receiving stationnotifies the sender to request these data blocks that must be resent.

2. Immune to poor channel events. Channel quality is ensured through acontrol loop based on the monitoring of channel conditions using beaconstrength measurements. Data transmission is simply ceased for theinfrequent periods when beacon strength falls below an acceptablethreshold level (e.g., rain fade events). Since the system isnon-real-time and non-continuous, occasional rain fade events have nomaterial effect on the service. For this reason the availability of theraw channel can be much less that that of real-time systems, greatlyreducing the size, cost and power of both the space and ground equipmentneeded to provide the service.

Furthermore the existence of this beacon signal also offers the systeman ability to adjust power level, bandwidth, or even closed-loop trackthe satellite's position to improve antenna pointing accuracy. Theability to control power levels is especially valuable in conservingbattery power on the satellite. The satellite's ability to service alarger number of customer transfers is a function of orbit parameters,but also is limited by an orbit average power budget. In one embodimentdescribed below, the overall bandwidth capacity is achieved bymultiplexing a number (e.g., four) channels. Should link quality degradean optional feature would allow all transmit power to be allocated toless channels, thus maintaining a quality link, but at a reducedbandwidth until fade conditions improve.

3. Interference friendly. Since all actions of the system are performedon a pre-determined basis and since the applications are allnon-real-time, the system can easily avoid transmitting alongpre-designated vectors such as the geostationary arc or ones that wouldintersect other low earth orbit systems, which would otherwise createsignal interference.

4. No data transfer protocol required. Since the system only supportsnon-real-time applications, it avoids the usual satellite communicationsneed for a data transfer protocol and the associated return channel.This means that the primary communications channel can be utilized at100% of designed capacity.

5. No complex multiple user access scheme required. The system servicesusers sequentially and allocates the full satellite capacity to only onesingle user at given a time. Therefore, there is no multiple user accessscheme employed by the system. This also allows for simple, and costeffective, very high data rate channelization of the bandwidth versustens or hundreds of individual lower rate channels more typically usedby satellite communications systems.

6. No signal latency issues. The system depicted herein, through itsfocus on file transfers, principally supports non-real-timeapplications. Therefore signal latency issues usually found withsatellite communications systems that try to support real-timeapplications such as phone conversations are not applicable.

7. No complex ‘on-demand’ satellite resource allocation required. Allactions by the system are pre-determined on the ground. The satellitecontrol facility only has to periodically uplink the scheduled actionsand then each satellite executes them as specified. Therefore, thesatellite does not have to make an autonomous decision about whichcustomers to serve, or when to serve them, significantly simplifying itsdesign. An optional feature would add a low bandwidth link to thesatellite that would allow a user to request data file pick-ups on anon-priority basis. As implemented, the serial servicing of users underthis alternative embodiment may remain, and the decision to accept a newpickup must only insure that this new action does not violate on-boardstorage limits, violate previously scheduled deliveries, violate thecurrent orbit's power budget, or other criteria.

8. No significant connectivity with terrestrial networks needed. Manysatellite communications systems depend on connectivity with terrestrialcommunications infrastructure to complete their service. This systemoperates essentially independent of terrestrial communicationsinfrastructure, moving data directly from the data source to thespecified data sink, although the terminus could be a fibre node whendesired.

9. Incremental system growth. Each satellite may operate independent ofevery other satellite in this system and the system users do not need tobe in continuous view of a satellite to be satisfied. Therefore, a largefleet of satellites is not needed to begin the service. The service canbegin with a limited number of satellites (e.g., one satellite), withadditional satellites deployed if or when demands warrant. This is incontrast to many other satellite communications systems (especiallythose that utilize non-geostationary orbits (NGSO)) where a large numberof satellites have to be completed and on orbit before any users can besupported.

10. All techniques that are described scale with available technologyelements. For example, optical satellite communications can besubstituted for radio frequency communications. Also as payloadequipment becomes available to support higher bandwidth newer satellitesand corresponding ground stations can be used to expand the service datarate capability.

11. The non real-time nature of the embodiment also allows terminals tobe constructed at lower cost. Lower orbits permit the use of smallerantennas which are easier to point, and when only one way transfers arerequired the terminal may be receive or transmit only. Also the antennasmay be pointed using a simplified open loop tracking embodiment in whichthe antenna pointing is based on a geometric calculation that uses thelocation and orientation of the terminal (as determined for example, byGPS and a compass) and the location of the satellite (as determined bytime from GPS and current ephemeris and orbital elements).

As described below, a digital satellite communications system and datatransfer method for the global movement of very large digital datafiles, ensures high data integrity, with delivery in less than a day.The system can handle very large data files, ranging currently from 50to 500 gigabytes and the extremely high data quality achieved, with biterror rates on the order of 10⁻¹⁶, which is approximately equivalent toone bit error per 10,000 delivered files of 100 gigabytes.

A. System Elements of Embodiment

As shown in FIG. 3, an embodiment of this invention is a system 300which includes a fleet of satellites 302 (with a communications payloadand supporting platform), a centralized planning function (referred toas Service Control 304), a centralized satellite control and taskingfunction (referred to as Mission Control 306) with a set of telemetry,tracking and command (TT&C) relays 308, and a number of ground terminals310 as architectural elements.

1. Satellite Fleet

The depicted embodiment of the invention in FIG. 3 includes a fleet oflow earth orbiting (LEO) satellites 302. The satellites in the fleet arecomposed of a communications payload and a supporting platform. Eachsatellite in the fleet has an assigned orbit, with the orbit inclinationof the satellites ranging from 60 to 70 degrees. This orbitalconfiguration of the fleet is chosen to meet the required global access.It is noted that a regimented orbital configuration is not necessary.Other embodiments may place the satellites into an orbital configurationwith variations on orbit altitude and inclination, which would alsoprovide significant global coverage, or be optimized around thedistribution of customer groups. The overall configuration of the fleetmay be that of a single fleet or subdivided to better meet groups ofuser's requirements including global locations.

Within the embodiment each satellite 302 operates independent of everyother satellite in the fleet. Each satellite has its own on-board massdata storage, with no requirement for inter-satellite links oroverlapping coverage. As well, the system users do not need to be incontinuous view of a satellite to be satisfied. Therefore, a large fleetof satellites is not needed to begin global coverage of the service.Service can begin with the launch of a single satellite, although toensure service reliability and shorter delivery times multiplesatellites are envisioned. The system can grow incrementally as demandgrows with the addition of new satellites to the fleet. Adding to thefleet enhances overall system capacity, reduces delivery time, and addssystem redundancy. This is in contrast to many other satellitecommunications systems where a large number of satellites have to becompleted and on orbit before any users can be supported, especiallywhen the source and destinations are widely separated.

While the embodiment does not require coordination or communicationbetween satellites, such additions can be deployed and provide anenhancement to data delivery times where that feature is important.

2. Satellite Payload

A system communications payload 312 provides the two-way directionaldata communications capability with ground terminals. The payloadconsists of these major parts: radio frequency (RF)/digital equipment400 and 403 through 409, a data storage unit 402, and a payloadcontroller 401. A simplified block diagram of payload components isshown in FIG. 4 (redundancy and switching is not shown).

The payload control computer 401 interfaces with the TT&C relay tocontrol the operation of the payload including antenna pointing asrequired. The RF/digital equipment is responsible for the high rate andhigh quality transmission and reception and the associatedanalog-digital conversions. The RF/digital equipment primarily consistsof a transmit/receive antenna 400 which can be pointed, a diplexor 409that allows simultaneous connection of uplink LNA 403 and down link HPA406 components, a set of high speed modems constructed from high ratemodulators 408/demodulators 405, associated up-converters407/down-converters 404 and various filters and switches. To provide theoverall capacity required for the end user bulk data store and forwardneeds, the total data transmit or receive rate is at least 1.2 gigabitsper second. To facilitate this high data rate the data uplink anddownlink is operated in the Ka-band, where sufficient spectrum isavailable. The total required data rate is achieved through theaggregate use of multiple lower rate channels (320 megabits per secondor greater). Both right-hand (RHC) and left-hand circular (LHC)polarizations and frequency diversity are used (with two channels perpolarization), and each channel is handled by a separate modem. Thechannel data rate used is restricted by the data rate limit ofmodulators and demodulators that are currently and affordably availableor that could be developed with low risk in the near term. However, theavailability of very much higher data rate modulators and demodulatorsis likely to occur in the future, permitting an embodiment with fewerchannels or operating at even higher data rates. The data link method isdescribed in more detail below.

Usage of other frequency bands are also suitable, provided that enoughspectrum is available and licenses may be obtained, even includingoptical communications in substitution for RF.

The data storage unit is a very high capacity, but low mass and powerefficient space qualified component. The unit allows each of thesmall-satellites to store over 6 terabits of data. The depictedembodiment of the data storage unit may be based on a redundant array ofindependent disks (RAID), or may be based on solid state data storagetechnology. Other data storage media are also possible. The data storagemethod is described in more detail below.

The payload has several modes, reflecting the fact that the payload mayoperate on a duty cycle basis. These modes include a low power mode forperiods of inactivity, a pre-operation mode to ready the payload toenter one of the operational modes by warming up various components, twooperational modes, and a safety mode that ensures the payload poses nothreat to the survival of the satellite. The two operational modes,which are mutually exclusive (although an alternate embodiment maypermit simultaneous reception and transmission with single or multipleusers within the beam footprint), are data packet receipt mode and datapacket transmission mode. In data packet receipt mode the antenna ispointed to acquire a specified set of latitude and longitude coordinatesthat has been designated as a stored command, the communications linkwith the transmitting ground terminal is initialized, and the user datais uplinked into on-board data storage. In a similar manner, when indata packet transmission mode, the payload antenna is pointed to acquirea specified set of latitude and longitude coordinates, thecommunications link with the receiving ground terminal is initializedand the user data is downlinked from on-board data storage.

A beacon signal is sent in the reverse direction (i.e. opposite from thedirection that is transmitting data packages) and is used to gatetransmissions and optionally to control power and/or bandwidth. Thebeacon may actively measure the characteristics of the transmission pathfrom all link loss sources.

3. Satellite Platform

Basic command and control functionality to operate and maintain eachsatellite 302 in the fleet is provided by a small-satellite platform314. In particular the satellite platform provides support services tothe communications payload.

High level functions performed by the satellite platform includeproviding an S-band interface to the ground (to Mission Control 306 viathe TT&C relays 308), autonomous satellite maintenance such as attitudeand orbit determination and control (using GPS as input data), powercontrol, thermal control, and fault detection, isolation and recovery(FDIR), as well as providing housekeeping and performance telemetry.While S-band is a common TT&C frequency band others may be used as well.

The satellite platform may also store pointing commands and possessesthe means to point the antenna toward the desired spot on the ground.Either body pointing, gimbaled or phased arrays techniques may be useddepending on size, cost or agility factors.

4. Ground Terminals

Ground terminals 310 provides access for a given user to the system, andthe service it provides. A feature of the invention is the capability tosupport ‘remote’ ground terminals. Remote ground terminals, either forland-based, vehicular, or marine applications, are located in isolatedregions (i.e. with limited communications infrastructure) and aretypically small, with antennas as small as approximately 1.2 meters indiameter.

Ground terminals provide the terrestrial end of the high rate Ka-bandlink with a satellite. (As used generally herein, the term “terrestrial”refers to not only land-based, but also ocean-based, lake-based, etc.)Ground terminals act as a data source (transmit) or a data sink(receive) for the user data files (i.e. point to point satellite datatransfer). Ground terminals may be transmit only, receive only, or bothtransmit and receive—but on a half duplex basis. Independent of the highdata rate Ka-band link to the satellites, the ground terminals interfaceto Service Control 304 through a low bandwidth connection, such asstandard terrestrial lines or a narrow-band satellite link such asdigital messaging over various satellite based phones or Inmarsat formarine applications.

The ground terminals communicate with Service Control using theequivalent of email messages. This low bandwidth link utilizes theconnectivity provided by pre-existing local communicationsinfrastructure, required by the user for other operational purposes. Theground terminals connect to the local communications infrastructure viaa standard internet protocol (IP) based local area network (LAN). Thelow bandwidth connection to the ground terminals is used by the systemto schedule and coordinate the service (i.e. data file pick-up anddrop-off activities), provide service status to the users, and tocoordinate and implement any data transmission that is requested toreplace erroneous data blocks.

When the user wishes to transfer a file it is copied (automatically) tothe originating ground terminal via a standard transfer protocol, suchas FTP. The originating ground terminal frames and codes the data fortransmission. The originating ground terminal makes a service requestand Service Control 304 schedules the data uplink and downlinkactivities with the originating and destination ground terminal as wellas a specific satellite (via Mission Control 306).

Once the data is received at the destination ground terminal the datablocks are decoded and correctable errors are fixed. Any data blockscontaining errors that are uncorrectable through the decoding processare listed to Service Control 304. Service Control initiates analternative data transfer of these listed bad data blocks between theoriginating and destination ground terminals via the low bandwidth link.Upon receipt of these new blocks the destination ground terminalreplaces the former bad data blocks. The rebuilt data is then placeddirectly into a local data archive or information system to be accessedby the user. The bit error rate prior to this extra layer of correctionis sufficiently robust using common FEC (Forward Error Correction) thatsuch a low bandwidth link is quite adequate. Other encoding may beperformed to facilitate error detection and correction/recovery at thegiven receiver (e.g., satellite, ground terminal or ultimate targetcomputer to receive the data file). If due to anomalous conditions theresend is excessive large the system may maintain the data in storageuntil verification is acknowledged, and the data may be retransmitted onthe next suitable satellite pass.

The ground terminal also employs a beacon signal that operates in theopposite path direction to the data communication (i.e. opposite fromthe direction that is transmitting data packages). The beacon is used tomeasure link quality and based upon that direct measurement thesatellite or ground terminal may gate its transmissions or adjust powerand/or bandwidth to maximize transfer effectiveness.

The planning and tasking method and the data error correction method aredescribed in more detail below.

As a means to further reduce delay in data delivery, or potentiallyreduce cost, the data may be relayed via intersatellite links to asecond satellite or via a ground relay. The ground relay would consistof a ground station that may be located where it can readily connect toother high bandwidth services or terrestrial links such as fibresystems. In this way the data may be delivered on an earlier satelliteorbit to a location that can easily pass it on to the destination.Reciprocally, this same relay embodiment may be used to source the datato the satellite for transmission to the remote terminal.

The terminals and following system elements may be implemented in or onany suitable computing platform or environment. Although not required,aspects of the invention are described in the general context ofcomputer-executable instructions, such as routines executed by ageneral-purpose computer, e.g., a server computer, wireless device orpersonal computer. Those skilled in the relevant art will appreciatethat the invention can be practiced with other communications, dataprocessing, or computer system configurations, including: Internetappliances, hand-held devices (including personal digital assistants(PDAs)), wearable computers, all manner of cellular or mobile phones,multi-processor systems, microprocessor-based or programmable consumerelectronics, set-top boxes, network PCs, mini-computers, mainframecomputers, and the like. Indeed, the terms “computer” and “terminal” aregenerally used interchangeably herein, and refer to any of the abovedevices and systems, as well as any data processor.

Aspects of the invention can be embodied in a special purpose computeror data processor that is specifically programmed, configured, orconstructed to perform one or more of the computer-executableinstructions explained in detail herein. Aspects of the invention canalso be practiced in distributed computing environments where tasks ormodules are performed by remote processing devices, which are linkedthrough a communications network, such as a Local Area Network (LAN),Wide Area Network (WAN), or the Internet. In a distributed computingenvironment, program modules may be located in both local and remotememory storage devices.

Aspects of the invention may be stored or distributed oncomputer-readable media, including magnetically or optically readablecomputer discs, hard-wired or preprogrammed chips (e.g., EEPROMsemiconductor chips), nanotechnology memory, biological memory, or otherdata storage media. Indeed, computer implemented instructions, datastructures, screen displays, and other data under aspects of theinvention may be distributed over the Internet or over other networks(including wireless networks), on a propagated signal on a propagationmedium (e.g., an electromagnetic wave(s), a sound wave, etc.) over aperiod of time, or they may be provided on any analog or digital network(packet switched, circuit switched, or other scheme). Those skilled inthe relevant art will recognize that portions of the invention reside ona server computer, while corresponding portions reside on a clientcomputer such as a mobile or portable device, and thus, while certainhardware platforms are described herein, aspects of the invention areequally applicable to nodes on a network.

5. Service Control

Service Control 304 is a software module that provides a centralizedplanning function for the system, coordinating on a pre-determined basisthe actions of all ground terminals and satellites and managingresources. All data movement related activities of the satellite fleetand of the ground terminals are scheduled, tasked and monitored byService Control. Service Control 304 tracks all user data in the system,coordinating any corrective measures necessary to ensure data quality ismaintained in the end-to-end transmission of the user data. Inparticular the functionality provided by Service Control includesinterfacing to the ground terminals 310, scheduling service, managingworkflow, interfacing with Mission Control (coordinate command andcontrol passes), tasking satellite payloads (via Mission Control),coordinating data block correction, and monitoring and maintainingground terminal network state of health.

Optionally the satellite 302 may contain a narrow band receiver ortransceiver that can receive a request directly from a usertransmitter/transceiver for data pick up and subsequent delivery. Thesatellite will examine the new request and determine if it is a validuser, and if in servicing the request there is a violation of any safetyor service criteria. Examples of these criteria include: on-board powermanagement, thermal loading, interference, adequate on-board storagereserves, slew rate of antennas, view angle of the ground stations, timeto next pass, etc.

6. Mission Control

Centralized satellite fleet control and tasking functions are providedby Mission Control 306. Mission Control is responsible for satellitemonitoring, maintenance and for translation and uplinking the satelliteactivities to be executed in support of data movement. In particularMission Control functionality includes generating satellite commandfiles, scheduling and tasking TT&C relay passes, tasking the satellitefleet (via the TT&C relays 308), processing satellite telemetry,verifying definitive orbits, generating predicted orbit data, andmonitoring and maintaining satellite fleet state of health.

7. TT&C Relays

A set of telemetry, tracking and command (TT&C) relays 308 provide anS-band or other suitable TT&C frequency interface between MissionControl and the satellite fleet. TT&C relays are programmed and taskedby Mission Control to carry out command and control passes withsatellites on a pre-determined schedule. The TT&C relays uplink acommand file to a satellite and downlink telemetry, to be forwarded toMission Control. These relays are considered part of Mission Control,although they may be external to the centralized Mission Controlfunction. They exist to enable frequent communications with thesatellite for safe monitoring and control, but also to upload currentschedule information for data pick-up and delivery events. Typically forNGSO systems such relays are at high latitudes that have line of sightcoverage at some point during most of the orbits.

The relay consists of a computer connected via reliabletelecommunications to mission control, and which is connected to atransceiver and steerable antenna system. The antenna tracks thesatellite and establishes reliable two way communications when thesatellite is in view. During such times the relay 308 uploads new dataincluding commands and software, and receives telemetry and other datafrom the satellite, which is transferred to mission control.

In a similar fashion to the incremental growth of the satellite fleetdescribed, the system can be managed with only one TT&C relay, with theaddition as needed of other TT&C relays reducing the time for thesatellites to be tasked and increasing system reliability.

8. End-to-end Data Flow Method

As illustrated in FIG. 5, an end-to-end data flow method 500 is used bythe system 300 to sequentially service users, by coordinating andtransferring user data, as scheduled by the centralized planningfunction (i.e. Service Control 304). This end-to-end method is supportedby a number of lower level methods, described in more detail herein,including:

-   -   planning and tasking method;    -   data link method;    -   data storage method;    -   rain fade method;    -   data error correction method; and    -   interference avoidance method.

To initiate the end-to-end data flow method, the user copies ortransmits the data file to local storage at the source ground terminal310, making it available to the system (step 501). The activitiesrequired by the system to transfer the data file are then planned byService Control 304 and the appropriate components of the system aretasked (step 502). The data file is broken into data blocks by theground terminal 310 and formatted (i.e. data is framed and FEC encodedusing well known techniques such as Reed-Solomon coding) for transfer(step 503).

At the beginning of a data pick-up pass (step 504) the boresight of thepayload antenna on the satellite 302 is directed to acquire a specifiedlatitude/longitude point and initializes a communications link with thetransmitting ground terminal 310. Uplink communication initializationincludes the ground terminal 310 transmitting a pattern at the start ofan uplink to allow the satellite demodulators to establishsynchronization (lock up). The system allows a few seconds forinitialization and then the satellite 302 begins recording the uplinkand the ground terminal 310 begins transmitting the user data (step509). In parallel the ground terminal monitors the beacon leveltransmitted by the payload 312 of the satellite 302 (step 505).

For uplink, in the case that rain fade is significant and the beaconlevel drops below an operational threshold, the ground terminal 310ceases transmission of the user data, instead transmitting fill data(step 506) in its place. The ground terminal continues to monitor thebeacon level (step 507). Once the beacon level returns to an operationallevel the ground terminal commences transmission of user data, startingwith on the order of the last few seconds of data before the beacondrop-out (step 508) in order or ensure continuity of data. Overlapping(i.e. duplicate) data blocks are identified in post-processing anddiscarded at the destination ground terminal 310. The continuoustransmission even of fill data can be important for proper operation ofthe high speed modems.

The data is stored on-board the payload 312 as the orbiting satellite302 is in transit (step 510), before the next scheduled activity. Thepresented embodiment does not perform any decoding or encoding on-boardthe satellite, however, the data is reconstituted in that the data isrecovered as bits which are stored and later remodulated forretransmission. (Under alternative embodiments, the satellite mayperform some or significant signal processing or dataanalysis/recovery.)

In a reciprocal fashion, at the beginning of a data delivery pass (step511) the payload antenna boresight is directed to acquire a specifiedlatitude/longitude point and initializes the communications link withthe receiving ground terminal. Downlink communication initializationincludes the satellite 302 transmitting a pattern at the start of adownlink to allow demodulators at the ground terminal 310 to synchronize(lock up). The system allows a few seconds for initialization and thenthe ground terminal begins recording the downlink and the satellitebegins transmitting the specified user data from on-board storage (step516). In parallel the satellite monitors the beacon level transmitted bythe ground terminal (step 512).

For downlink, in the case that rain fade or other degradation issignificant and the beacon level drops below an operational threshold,the satellite 302 ceases transmission of the user data, insteadtransmitting fill data (step 513). The satellite continues to monitorthe beacon level (step 514). Once the beacon level returns to anoperational level the satellite commences transmission of user data,starting with on the order of the last few seconds of data before thebeacon drop-out (step 515). Again, this ensures continuity of data.

Once the user data is received from the satellite 302 at the destinationground terminal 310, it is decoded, any correctable errors are fixed,and any transmission errors that are identified as uncorrectable throughthe FEC (Reed-Solomon or other common FEC coding scheme) decodingprocess are listed for Service Control 304 (step 517). The systemcoordinates the re-sending of the very few specific data blockscontaining uncorrectable errors through an alternate low bandwidthcommunication link (step 518). The destination ground terminal thencorrects the errors by replacing the bad data blocks (step 519) andmakes the data available to the user, either locally or via high-speednetworks (step 520). The overall effect of cascading these techniquesresults in extremely low bit error rates (e.g. ˜10 E-16).

For the uplink or downlink, in the case that interference avoidance isrequired (not shown), the pass may be broken up into two separatesegments, with a gap (i.e. exclusion zone) as required during which alltransmissions are turned off.

B. Methods/Subroutines

1. Planning and Tasking Method

In this embodiment the coordination of the system is performed by acentralized ground-based planning function (i.e. Service Control 304).This coordination includes deciding which user to serve, and when, aswell as deciding on how to utilize system resources to best provide thisservice. The satellites do not have to make an autonomous decision, theyonly need to follow the specified actions that have been uplinked fromthe ground. In an alternate embodiment the satellite may accept somerequests from the ground users directly and integrate them with theinstructions from the ground, but with restrictions that these requestsmust not conflict with ground instructions, priorities, or satelliteoperational limits (e.g., orbit average power battery restrictions ormemory capacity limits).

System control software manages resources, such as satellite on-boardmemory and power usage. The management of the satellite on-board filesystem is also performed on the ground, as part of resource planning. Itis noted that alternatively file system management could be doneon-board the satellite 302 itself. Conflicting service demands areresolved and large data packages are broken up into smaller ones toapproach an optimized schedule. Schedule interruptions introduced tomanage interference issues with other systems (e.g., geostationary arc)are also planned. The centralized planning function pre-determines therequired schedule of interactions between the satellite fleet and theground terminals.

The satellites and ground terminals are then periodically tasked basedon the pre-determined schedule of interactions, which simplifies theoverall system design. Specific tasks are uplinked to the satellitesusing a network of telemetry, tracking and command (TT&C) relays 308,via Mission Control 306. The ground terminal communicate with thecentralized planning function, using the equivalent of email messages,to coordinate the scheduled activities including the data pick-up anddrop-off passes and any low bandwidth link for error correction.

This planning and tasking method is low risk since the system only hasto support a few large users versus more usual satellite communicationssystems that try to serve many very small and diverse users. Allocationof large file pick-up and drop-off service to users is analogous to theallocation schemes used by earth observation satellites—this embodimentdoes not have to perform complicated dynamic on-demand allocation of thesatellite resource usually seen in satellite communication systems. Itis noted that other planning and tasking methods could also be used.

The system, through its focus on files transfers, avoids signal latencyissues usually found with satellite communications systems that try tosupport applications, such as phone conversations, and are notapplicable.

The system may also ensure that satellite ephemeris and orbital elementsare managed by the ground control system and made available to theantenna tracking algorithms so that the open loop tracking method isalways as accurate as necessary.

2. Data Link Method

The system may operate the high-speed space to ground data link in theKa spectrum band, within specific frequency allocations for both thedownlink and the uplink. Alternatively, other bands or optical links areapplicable that provide enough fractional bandwidth for the necessarydata rates and that they may be licensed for such purposes.

A single-user access scheme is employed by the system, allocating thefull satellite link capacity to a given user, one at a time (although inalternative embodiments, the satellite may handle several concurrentusers). This also allows for simple very high data rate channelizationof the bandwidth. Other satellite communications systems typicallyemploy a multi-user access scheme, with tens or hundreds of individuallower rate channels. Additionally the system operates as half duplex, sothere is no simultaneous data transmit and receive, however a fullduplex system could be used.

For the depicted embodiment the aggregate bandwidth, on the order of 1.2gigabits per second, is provided by four asynchronous channels, althoughhigher rates may evolve as technology and user requirements grow overtime. Specifically both right-hand and left-hand circular polarizationsand frequency diversity are used with each polarization split into twochannels. Each of these four channels is handled by a separate modem(see FIG. 4). It is noted that alternate channelization schemes canachieve an equivalent bandwidth, such as fewer but higher rate channels.However, the depicted embodiment reduces cost and technical risk becauseof the present availability of these space qualified modulators andparticularly these demodulators.

The uplink and downlink signal modulation may be QPSK, or offset-QPSK,with the data differentially encoded by source ground terminals to allowI/Q and polarity ambiguities to be resolved at the receiving(destination) ground terminal. No added coding nor decoding of the datais performed by the satellite, other than that required to convert thedemodulator output to data bits for storage and the reciprocal processfor remodulation. This data reconstitution avoids the increase in noiselevel that arises from “bent pipe” analog transponders, but requires nointelligence on board the satellite to discern the nature of the datathat is being transferred for the user. It is noted that other signalmodulation and data encoding schemes are also feasible.

The system does not require a data transfer protocol and therefore thesatellite manages the bit stream at the link layer. Since the systemsupports non-real-time applications, it avoids the usual satellitereal-time communications need for a data transfer protocol, withcorresponding overhead, and the associated return channel. This meansthat the primary communications channel can be utilized at 100% ofdesigned capacity.

3. Rain Fade Method

A beacon signal is included in the system design for supporting closedloop antenna tracking, which is especially useful for ship borne groundterminals. However, as a key dual benefit, a method for eliminating thechance of sending data during high rain fade or other disadvantagedconditions takes advantage of the presence of a beacon signal. It doesso without any need for two way communications with the source oftransmissions. This is an important feature of the invention since atKa-band (and many other very high RF and optical communications bands)the rain fade of the signal can be significant. The monitored beaconsignal level is used for flow control of the data transmission. Thebeacon signal level may also be used to control transmit power to allowreduction of the effective isotropic radiated power (EIRP) with a goodlink to preserve battery capacity. Alternatively, the bandwidth may beadjusted to focus all the amplifier (HPA) power under marginal linkcondition

The beacon may be a narrow-band signal that is pseudorandom (PN) codemodulated to spread the spectrum within the frequency spectrum allocatedfor data transmission on the uplink or downlink. An alternate embodimentof the beacon may be an un-modulated narrow-band signal within theallocated frequency spectrum. The received beacon level may be low passfiltered before using it to determine the path condition.

The transmitting end of the link monitors the strength of the beaconsignal, and transmits dummy fill data when the beacon signal strength isbelow the operational threshold, a minimum E_(b)/N₀ or C/N. Each channelmay have a separate estimate for this beacon signal level measurement.The process employs hysterisis between the poor and the good receivedbeacon level thresholds to prevent excessive switching between the goodand poor levels. Beacon reception is simultaneous with datatransmission, and beacon transmission is simultaneous with datareception. The beacon signal generation and monitoring may be performedwithout adding separate beacon-specific transmit/receive chains. The useof a data transfer protocol to ensure data fidelity, instead of usingthe described rain fade method, would reduce the system efficiency.

Just prior and during the data uplink from a ground terminal 310, thepayload 312 can downlink the beacon. This beacon can be monitored by theground terminal 310 to facilitate tracking and to determine pathconditions. If the path conditions are too poor to permit low errortransmission of data to the satellite, the ground terminal can stoptransmitting data until such time as the beacon signal strengthimproves, and can instead transmit dummy fill data. This process isreversed for the case where the satellite 302 is downlinking data to aground terminal. The ground terminal may uplink the beacon for thesatellite to monitor path conditions and for payload antenna tracking.If the path conditions are too poor to permit low error transmission ofdata to the ground terminal, the satellite can stop transmitting data,and can instead transmit dummy fill data, until such time as the beaconsignal strength improves.

4. Data Storage Method

The depicted embodiment of the invention includes a high capacity datastorage method as a part of the store and forward operation, with atotal storage capacity currently sized at about 6 terabits. The datastorage embodiment may have a separate data storage unit for each of thefour data channels, each channel handled asynchronously and in parallel.The data storage units may be a redundant array of independent disks(RAID). This is basically a small coordinated group of commerciallyavailable, space qualified, high capacity computer hard drives that aremounted so as not to introduce unwanted angular momentum or disturbancetorques. However, other data storage media, including solid statestorage technology, could also be used as an alternative embodiment,especially as solid state memory device densities continues to riserapidly.

The coded and framed bit stream is inputted in raw form into datastorage, and transmitted in raw form from data storage, so no specialprocessing or switching is required on-board the satellite 302, whichsimplifies the payload design. The data storage units are designed forhigh speed read and write, including random addressing andaccessibility, with data handled in blocks at a resolution currently ofapproximately 4 megabytes. File management of the on-board data blocksis performed on the ground by Service Control 304 through the upload ofpre-determined actions, also simplifying the payload design.

The data storage units are designed to operate in a space environment,with low power consumption, and a reasonable size and mass compared toother data storage options. The data storage units are also designed forhigh reliability, to facilitate data integrity and satellite lifetime.

The storage may have a high speed input/output data path that matchesthe modem data rates, and the ability to randomly access each user'sdata for independent transmission. It is recognized that othervariations on this embodiment for data storage could be used to meet therequired high capacity and high speed requirements.

5. Data Error Correction Method

The data link method will inevitably introduce errors into the userdata, with these errors tending to be a mixture of random bit errors andburst errors. To ensure data integrity through virtually error-freetransmission, with a bit error rate on the order of 10⁻¹⁶ (approximatelyequivalent to one bit error per 10,000 delivered 100 gigabyte files),the system uses a combination of the following techniques to augment thedata link:

-   -   Data Coding Method;    -   Data Re-Retransmission Method (few bad blocks); and    -   Data Re-Transmission (major data block loss) Method.

a. Data Coding Method

A technique of the invention for the detection and correction oftransmission errors is Forward Error Correction (e.g., Reed-Solomon)coding of the data. The embodiment of the system uses an interleavedReed-Solomon forward error correction method to correct the majority oftransmission bit errors and detect uncorrectable errors. No otherencoding or decoding is performed by the satellites, which adds slightlyto the data overhead stored on-board, but also greatly reduces thecomplexity of the satellite payload.

This data coding technique is illustrated in FIG. 6. User data may betransmitted via the satellite in data blocks. The size of these datablocks may be selected but is shown as 1024 bytes of user data plusapproximately 17% overhead for framing and error correction encoding.The transmitted data blocks may be composed of five interleaved ReedSolomon error correction blocks, with a Reed Solomon (255,223) codeused. It is noted that other encoding may be used under alternativeembodiments. The Reed Solomon encoding is performed by the originatingground terminal 310. Upon receipt of the user data the destinationground terminal decodes the data, checks for errors and automaticallycorrects any identified errors, when possible, using the Reed Solomonencoded information. Errors detected through the Reed-Solomon decodingprocess that are not directly correctable are listed to Service Control.This technique produces BER levels that are approximately 10 E-8 alone.

b. Data Re-Transmission Method (Few Bad Blocks)

The second technique for data error correction is for the destinationground terminal to use a low speed channel or alternate satellite orterrestrial link to retrieve new data blocks that had containeduncorrectable errors from the originating ground terminal. Data blocksreceived with uncorrectable errors at the destination ground terminalare identified through the Reed-Solomon decoding process and a list ofthese bad blocks is provided to Service Control 304. Service Controlthen coordinates with the originating ground terminal 310, usingstandard email type messages, to send new data blocks for thedestination ground terminal to replace the corrupted data blocks. Thistechnique is illustrated in FIG. 6.

This low speed link may be a dial-up, internet, or modem connection viastandard low-bandwidth communication mechanisms already in place betweenthe receiving and transmitting ground terminals (e.g., terrestrial linesor Inmarsat). This conventional low speed link is independent of theCascade™ satellite or fleet of satellites.

The minimum recommended speed of this connection to support the systemis 9600 bits per second. The data recovery method is feasible since thenumber of uncorrectable errors will be very small for data files underthe above embodiment, typically requiring no more than a few minutes atthis 9600 bits per second data rate to obtain the required data blocksfrom the originating ground terminal. In an extreme case the number ofdata blocks requested by this method may be automatically limited, basedon the actual connection data rates, to be less than the cost of a thethird method below for data recovery.

c. Data Re-Transmission Method (Major Data Loss)

As a third error correction technique, if there are a large number ofdata blocks with uncorrectable errors (rare), the data blocks arere-transmitted either directly from the data storage on-board thesatellite or from the originating ground terminal via the satellitefleet. The destination ground terminal would then replace the bad datablocks with the new data blocks in the same way as for the prior datarecovery method. The use of this data re-transmission method, as opposedto the previous method, is decided and coordinated by Service Control.The data re-transmission technique is illustrated in FIG. 6.

6. Interference Avoidance Method

Since all actions of the system are ultimately controlled on apre-determined basis by Service Control and since the applications areall non-real-time, the system can easily avoid transmitting alongpre-designated vectors, such as the geostationary arc, or ones thatwould intersect other non-geosynchronous orbit (NGSO) systems.

The satellite and ground terminal may perform data transfer passes, aspreviously described, until a pre-determined service null vector isreached. At that point all transmissions by the satellite and the groundterminal are terminated. Once the system has passed such a service nullvector, typically a small portion of a given data transfer pass with thesatellite, the transmission can re-commence. All these interferenceavoidance activities are pre-determined and scheduled by Service Controlas part of normal system tasking. Therefore, the embodiment of thissystem is inherently interference friendly and easily coordinated withother systems using the same frequencies.

To minimize the need for the satellite to carry a complex and changingtabulation of ephemeris data and compute the blanking intervals itself,the management of transmission blanking is calculated on the ground bymission control and uplinked via the TT&C relays to the satellite ascommand data.

C. Conclusion

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words ‘comprise’, ‘comprising’, and thelike are to be construed in an inclusive sense as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to”. Words using the singular or pluralnumber also include the plural or singular number, respectively.Additionally, the words “herein,” “above” and “below” and words ofsimilar import, when used in this application, shall refer to thisapplication as a whole and not to any particular portions of thisapplication. When the claims use the word “or” in reference to a list oftwo or more items, that word covers all of the following interpretationsof the word: any of the items in the list, all of the items in the list,and any combination of the items in the list.

The above detailed description of embodiments of the invention is notintended to be exhaustive or to limit the invention to the precise formdisclosed above. While specific embodiments of, and examples for, theinvention are described above for illustrative purposes, variousequivalent modifications are possible within the scope of the invention,as those skilled in the relevant art will recognize. For example, whileprocesses or blocks are presented in a given order, alternativeembodiments may perform routines having steps, or employ systems havingblocks, in a different order, and some processes or blocks may bedeleted, moved, added, subdivided, combined, and/or modified. Each ofthese processes or blocks may be implemented in a variety of differentways. Also, while processes or blocks are at times shown as beingperformed in series, these processes or blocks may instead be performedin parallel, or may be performed at different times. Where the contextpermits, words in the above Detailed Description using the singular orplural number may also include the plural or singular numberrespectively.

The teachings of the invention provided herein can be applied to othersystems, not necessarily the system described herein. The elements andacts of the various embodiments described above can be combined toprovide further embodiments.

All of the above patents and applications and other references,including any that may be listed in accompanying filing papers, areincorporated herein by reference. Aspects of the invention can bemodified, if necessary, to employ the systems, functions, and conceptsof the various references described above to provide yet furtherembodiments of the invention.

These and other changes can be made to the invention in light of theabove Detailed Description. While the above description details certainembodiments of the invention and describes the best mode contemplated,no matter how detailed the above appears in text, the invention can bepracticed in many ways. Details of the data transfer system may varyconsiderably in its implementation details, while still beingencompassed by the invention disclosed herein. As noted above,particular terminology used when describing certain features or aspectsof the invention should not be taken to imply that the terminology isbeing redefined herein to be restricted to any specific characteristics,features, or aspects of the invention with which that terminology isassociated. In general, the terms used in the following claims shouldnot be construed to limit the invention to the specific embodimentsdisclosed in the specification, unless the above Detailed Descriptionsection explicitly defines such terms. Accordingly, the actual scope ofthe invention encompasses not only the disclosed embodiments, but alsoall equivalent ways of practicing or implementing the invention underthe claims.

While certain aspects of the invention are presented below in certainclaim forms, the inventors contemplate the various aspects of theinvention in any number of claim forms. For example, while only oneaspect of the invention is recited as embodied in a computer-readablemedium, other aspects may likewise be embodied in a computer-readablemedium. Accordingly, the inventors reserve the right to add additionalclaims after filing the application to pursue such additional claimforms for other aspects of the invention.

1. A system for transmitting large data files of at least an aggregated100 gigabytes from a source terminal to a geographically distantdestination terminal in substantially non-real-time, the systemcomprising: at least one satellite in a non-geostationary orbit, whereinthe satellite is configured to store and forward data files andincludes: a wireless transceiver, mass data storage, and at least oneprocessor coupled among the wireless transceiver and the mass datastorage; and at least first and second terrestrial or sea-basedstations, wherein the first station has at least a wireless transmitterand is configured to receive a large data file from the source terminal,wherein the large data file represents an aggregate of least 100gigabytes, process the large data file for transmission by at leastencoding the large data file with block coding and forward errorcorrection, and transmit the large data file to the satellite at apredetermined time, wherein the large data file includes an electronicaddress for the destination terminal; wherein the second station has atleast a wireless receiver and is configured to receive the large datafile from the satellite and transfer the large data file to thedestination terminal based in part on the electronic address for thedestination terminal; wherein the satellite stores the large data filefor more than several minutes before transmitting it to the secondstation; wherein at least the first station or satellite are furtherconfigured to monitor a signal quality from a beacon channel for anindication that a wireless channel with the satellite is of acceptablequality before the large data file is transmitted over the wirelesschannel, or configured to monitor the signal quality from the beaconchannel and suspend transmissions, adjusting power or adjusting abandwidth for communications over the wireless channel based on themonitored signal quality; and wherein the first and second stationsfurther each include transceivers for communicating over a low bandwidthcommunication channel, wherein the low bandwidth communication channelis of a much lower bandwidth than the wireless channel, and wherein thesecond station is further configured to detect blocks of data in thereceived large data file that contain uncorrectable errors and requestthe first station to retransmit, over the low bandwidth communicationchannel, any data blocks from the large data file that contain errors,whereby the system provides a bit error rate (BER) on an order of atleast 10⁻¹⁵.
 2. The system of claim 1 further comprising multiplesatellites in low earth orbit, wherein the wireless channel isapproximately in the Ka band to provide very high bandwidth, whereineach of the multiple satellites operate independent of each other, andwherein at least the first station is configured to monitor a quality ofthe wireless channel and adjust the encoding of the large data file inresponse thereto; wherein the low bandwidth channel is an alternate linkbetween the first and second stations; and wherein the second stationrequests at least the satellite to retransmit the large data file if thesecond station detects significant loss of data blocks in the large datafile.
 3. The system of claim 1 wherein the first station is on a vesselor vehicle, and wherein the satellite and the first station areconfigured to: employ closed loop tracking between the satellite and thefirst station, via the beacon channel, to control pointing of at leastthe satellite or the first station.
 4. A non-transitorycomputer-readable medium whose contents cause at least one land- orsea-based communications terminal to perform a method to process datafor wireless transmission to at least one satellite in anon-geostationary orbit, wherein the satellite is configured to storeand forward data packages to a destination terminal, the methodcomprising: at the communications terminal, receiving at a first time alarge data file of at least 10 gigabytes at the communications terminal,dividing the large data file into multiple smaller groups of data; atthe communications terminal, coding the large data file for errorcorrection after transmission of the large data file; determiningwhether a quality of a wireless, high bandwidth communications channelwith the satellite is acceptable; at the communications terminal, and ata second time after the first time, transmitting the divided and codedlarge data file to the satellite when the quality of the wireless, highbandwidth communications channel is acceptable and when the satellite isat an originating geographic location; and providing information to thesatellite regarding the destination terminal, wherein the satellitestores the divided and coded large data file until the satellite iswithin sight of the destination terminal for transmission to thedestination terminal at a third time, wherein the third time is at leasttwo minutes after the second time, and wherein the destination terminalis geographically remote from the originating geographic location
 5. Thecomputer-readable medium of claim 4 wherein the computer-readable mediumis a memory of the telecommunications server.
 6. The computer-readablemedium of claim 4 wherein the method further comprises: detecting groupsof data in the large data file that contain uncorrectable errors, andrequesting retransmission, over a low bandwidth communication channel,any data groups from the large data file that contain errors.
 7. Thecomputer-readable medium of claim 4 wherein the method furthercomprises: monitoring a quality of the wireless, high bandwidthcommunications channel and adjusting the dividing or coding of the largedata file in response thereto.
 8. The computer-readable medium of claim4 wherein the method further comprises: detecting significant loss ofdata groups in the large data file, and requesting retransmission of allor a significant part of the large data file.
 9. The computer-readablemedium of claim 4, further comprising inserting fill blocks instead ofgroups of the data when the high bandwidth communications channel isunacceptable.
 10. The computer-readable medium of claim 4 whereindividing the large data file includes block coding the large data file.11. The computer-readable medium of claim 4 wherein coding the largedata file includes forward error correcting the large data file.
 12. Thecomputer-readable medium of claim 4 wherein receiving the large datafile includes receiving the large data file form a terminal located on avehicle or sea vessel.
 13. The computer-readable medium of claim 4wherein coding the large data file includes encrypting the large datafile form a terminal located on a vehicle or vessel.
 14. Thecomputer-readable medium of claim 4, further comprising a satellitephone link or another satellite link to transmit a small number of datapackets to the destination terminal to replace at least one group ofdata having errors.
 15. In a communications system employing at leastone satellite in a non-geostationary orbit configured to store largedata files from a source terminal, and forward the data files to ageographically distant destination terminal, a method for controllingwireless telecommunications in the system comprising: monitoring abeacon channel between the satellite and at least the source ordestination terminals, wherein the beacon channel provides an indicationof a quality of at least one high bandwidth wireless channel between thesatellite and the source or destination terminals; determining a qualityof the high bandwidth wireless channel based on the monitoring of thebeacon channel; and postponing transmission of all or portions of alarge data file over the high bandwidth wireless channel if thedetermined channel quality is unacceptable, or adjusting a bandwidth forcommunications over the high bandwidth wireless channel based on thedetermined channel quality, wherein the satellite receives and stores alarge data file at the source terminal, wherein the satellite transmitsthe large data file at least two minutes later to the geographicallydistant destination terminal, and wherein the large data file is atleast an aggregated 10 gigabytes.
 16. The method of claim 15, furtheremploying the beacon channel to control power of transmissions from thesatellite.
 17. The method of claim 15, further employing the beaconchannel to control pointing of the satellite with respect to either thesource or destination terminal.
 18. In a wireless communications system,an apparatus for controlling data transmissions with respect to at leastone non-geostationary orbiting satellite, wherein the satellite isconfigured to store and forward data packages between land- or sea-basedterminals, the apparatus comprising: means for monitoring a beaconchannel, wherein the beacon channel provides an indication of a qualityof at least one high bandwidth wireless channel between the satelliteand a land- or sea-based terminal; means for signaling the satellite,based on the monitored channel quality, to transmit a large data packageover the high bandwidth wireless channel if the channel quality isacceptable, or postpone transmission of a large data package over thehigh bandwidth wireless channel if the channel quality is unacceptable,or adjust a transmit power and/or adjust a bandwidth for communicationsover the high bandwidth wireless channel if the channel quality isbetween acceptable and unacceptable; and means for communicating underat least a simplex transmission scheme over the high bandwidth channelwith the satellite.
 19. The apparatus of claim 18, further comprising:satellite ephemeris means for determining a location of the satellite;terminal location means for determining global positioning location andland- or sea-based antenna orientation; and means for coordinating datatransmission or reception from the satellite based on the satelliteephemeris means and the terminal location means.
 20. The apparatus ofclaim 18 wherein the means for communicating includes means forcommunicating under a duplex or half-duplex transmission scheme over thehigh bandwidth channel with the satellite.
 21. The apparatus of claim 18wherein the means for communicating includes means for providing anelectronic address of a destination associated with the large datapackage, wherein the electronic address is a set of latitude andlongitude coordinates, an account or identification number, or auniversal resource locator (URL).
 22. The apparatus of claim 18, furthercomprising: antenna means; satellite tracking means for determining alocation of the satellite; and antenna pointing means for generatingantenna pointing instructions for directing the antenna means toward thesatellite, wherein the antenna pointing instructions provide mechanicalor phased array pointing instructions.
 23. The apparatus of claim 18,further comprising: satellite tracking means for determining a locationof the satellite; and antenna pointing means for generating antennapointing instructions for the satellite, wherein the antenna pointinginstructions provide gimbaled antenna or whole satellite body movinginstructions to the satellite.
 24. The apparatus of claim 18, furthercomprising: beacon tracking means for automatically tracking the beaconchannel.
 25. The apparatus of claim 18, further comprising: relay meansfor receiving the large data package from the satellite and forwardingthe large data package via terrestrial links to a desired destination.26. The apparatus of claim 18, further comprising: means for instructingthe satellite to not transmit the large data package when a transmitpath from the satellite intersects a vector that potentially couldinterfere with transmissions.